Hydride Vapor-Phase Epitaxy Reactor for Bulk GaN Growth

An hydride vapor-phase epitaxy reactor for the growth of bulk GaN crystals with a diameter of 50 mm is developed. Growth rate nonuniformity of 1% is achieved using an axisymmetric vertical gas injector with stagnation point flow. Chemically resistant refractory materials are used instead of quartz in the reactor hot zone. High-capacity external gallium precursor sources are developed for the nonstop growth of the bulk GaN layers. A load-lock vacuum chamber and a dry in situ growth chamber cleaning are implemented to improve the growth process reproducibility. Freestanding GaN crystals with a diameter of 50 mm are grown with the reactor.